Nike is basically the protagonist of the story, though he's not your typical hero type. His dad had always dreamed of being a hero himself but never got the chance—there just wasn't enough evil in the world to fight back then. So instead, he poured all that unfulfilled ambition into training Nike as a kid, banking on the hope that someday a real threat would show up. It worked in terms of making Nike competent in a fight, but the guy's also kind of a coward about it, and early on he's pretty immature and inexperienced, which puts him in the same boat as Kukuri in that regard.
Nike comes from Jimuna Mura—basically "Plain Old Town"—and he's not exactly thrilled about the whole hero thing at first. His parents basically push him into it anyway.
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